A crawler transport robot and its center of gravity control method

Abstract

A crawler transport robot and a method for controlling its center of gravity, the crawler transport robot comprises a body, a power device, a transmission device, a walking device, a bearing device, a control device and a center of gravity balancing device, the transmission device is respectively connected to the power device and the walking device, the control device is connected to the power device, and the center of gravity balancing device comprises: a transverse slide rail, one end of which is equipped with a transverse stepper motor; a longitudinal slide rail, one end of which is equipped with a longitudinal stepper motor; a counterweight block, which is installed on the longitudinal slide rail; a pressure sensor; an angle sensor; a binocular camera and a center of gravity controller, which drives the transverse stepper motor or the longitudinal stepper motor to move according to a preset center of gravity control method, and the counterweight block moves in real time with the body posture and the obstacles in front, so as to realize the real-time adjustment of the robot's center of gravity. The present invention also provides a method for controlling the center of gravity of the crawler transport robot to improve its driving and obstacle-crossing operation safety in hilly orchards.

Description

Technical Field

[0001] The invention relates to an agricultural transport device, in particular to a crawler transport robot suitable for hilly orchards and a gravity center control method thereof. Background Art

[0002] my country is the world's largest fruit producer and consumer. Fruit production in hilly and mountainous areas is an important part of my country's fruit industry. In the process of fruit production, a large amount of labor is required in the transportation of agricultural materials and the transportation of fruits. With the improvement of the domestic urbanization level, the number of rural laborers has decreased year by year, the production cost has increased year by year, and the economic benefits of fruit farmers have declined significantly. Therefore, transportation machinery suitable for hilly and mountainous orchards is of great significance to the further development of my country's fruit industry.

[0003] Due to the characteristics of small plots, complex terrain conditions, and narrow mechanized farming roads in mountain orchards, traditional wheeled agricultural machinery chassis used in large fields are prone to rollover and slipping when operating in mountain orchards, posing a major safety hazard. The crawler chassis has the advantages of low ground contact pressure, strong load capacity, large traction, and good terrain adaptability, and is currently a preferred solution for the power chassis of mountain orchards.

[0004] In recent years, many brands of crawler orchard transporters have appeared in the domestic and foreign markets. Most of them complete orchard transportation operations by installing a fruit loading platform on the upper part of an ordinary crawler chassis. Although they have better terrain passability than ordinary wheeled chassis and can adapt to mountain orchard operating conditions to a certain extent, such orchard transporters are not specifically designed for the actual terrain and landform characteristics of mountain orchards and the slope driving environment, and they do not consider the impact of changes in the weight of the fruit carried on the upper part on the actual driving performance of the chassis. There are still major problems in slope driving stability and obstacle passability. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a crawler transport robot suitable for hilly and mountainous orchards and a center of gravity control method thereof in response to the above-mentioned defects of the prior art. The robot can adjust the center of gravity position in real time according to the body posture, load weight and type of obstacles ahead, thereby improving the robot's slope driving performance and realizing stable material transportation in hilly and mountainous orchards.

[0006] In order to achieve the above-mentioned object, the present invention provides a crawler transport robot, comprising a body and a power device, a transmission device, a walking device, a bearing device and a control device installed on the body, wherein the transmission device is connected to the power device and the walking device respectively, and the control device is connected to the power device, wherein the robot further comprises a center of gravity balancing device, the center of gravity balancing device is located in the body, and the center of gravity balancing device comprises:

[0007] A transverse slide rail is installed on a bracket in the body, and a transverse stepping motor is installed at one end of the transverse slide rail;

[0008] A longitudinal slide rail is installed on the transverse slide rail and moves along the transverse slide rail, and a longitudinal stepping motor is installed at one end of the longitudinal slide rail;

[0009] A counterweight block is mounted on the longitudinal slide rail and moves along the longitudinal slide rail;

[0010] A pressure sensor, installed at the connection between the body and the carrying device, for real-time monitoring of the pressure of the carrying device on the body;

[0011] An angle sensor, installed near the centroid of the machine body, for real-time monitoring of the inclination angle change of the machine body;

[0012] A binocular camera, mounted on the front of the robot body, for real-time monitoring and identifying obstacles in front of the robot; and

[0013] A center of gravity controller is installed in the body, and the center of gravity controller includes an industrial computer and a stepper motor driver. The industrial computer is connected to the pressure sensor, the angle sensor and the binocular camera respectively, and receives pressure data, angle data and image data collected by the pressure sensor, the angle sensor and the binocular camera in real time. The stepper motor driver is connected to the horizontal stepper motor and the longitudinal stepper motor respectively. The industrial computer inputs a control signal into the stepper motor driver according to a preset center of gravity control method, and the stepper motor driver drives the horizontal stepper motor or the longitudinal stepper motor to move accordingly. The counterweight block moves in real time with the body posture and the obstacle in front, so as to realize real-time adjustment of the center of gravity of the robot.

[0014] The above-mentioned crawler transport robot also includes an alarm, which is connected to the industrial computer and is used to alarm the robot's tipping over during driving. When the robot's tilt angle approaches the limit safety angle under the current load or the robot cannot safely pass the obstacle ahead, the alarm will issue an alarm prompt.

[0015] The above-mentioned crawler transport robot, wherein the longitudinal slide rail includes a longitudinal slide rail, a longitudinal slide table and a ball screw, the ball screw and the longitudinal slide rail are respectively arranged parallel to the longitudinal slide table, the counterweight block is installed on the longitudinal slide table, the longitudinal stepping motor is connected to the ball screw, and drives the ball screw to drive the counterweight block to slide along the longitudinal slide rail.

[0016] The above-mentioned crawler transport robot, wherein the transverse slide rail includes a first transverse slide rail and a second transverse slide rail, the first transverse slide rail includes a first transverse slide rail, a first transverse slide table and a lead screw, the lead screw and the first transverse slide rail are respectively arranged parallel to the first transverse slide table, the transverse stepping motor is connected to the lead screw, and drives the lead screw to drive the longitudinal slide rail and the counterweight block to slide along the first transverse slide rail; the second transverse slide rail includes a second transverse slide rail and a second transverse slide table, which are used to support the longitudinal slide rail and the counterweight block.

[0017] The above-mentioned tracked transport robot, wherein the center of gravity controller calculates the real-time center of gravity position of the entire robot based on the angle data and pressure data, takes the equal ground contact pressure of the tracks on both sides of the walking device as the control condition, and drives the transverse stepper motor and the longitudinal stepper motor through the stepper motor driver to control the position of the counterweight block to adjust the center of gravity of the entire machine.

[0018] In the above-mentioned crawler transport robot, the center of gravity controller calculates the robot's limit inclination angle under the current load condition while calculating the real-time center of gravity position of the whole machine. If the current inclination angle is close to the robot's limit inclination angle, the alarm will sound.

[0019] The above-mentioned tracked transport robot, wherein the center of gravity controller performs real-time estimation of the camera position and posture and three-dimensional mapping of the ground in front based on the visual SLAM algorithm according to the image data and depth data in front of the robot collected by the binocular camera, and judges whether there is an obstacle in front of the robot and the type of obstacle based on the result of the three-dimensional mapping.

[0020] The above-mentioned tracked transport robot, wherein the center of gravity controller is based on the processing results of the visual SLAM algorithm. If it is determined that the obstacle ahead is a vertical obstacle, it first determines whether the current height of the vertical obstacle exceeds the maximum obstacle crossing height under the robot's current load conditions. If it exceeds, the robot cannot climb over it, and the alarm will sound; if it can climb over it, based on the real-time position and posture estimation results of the visual SLAM, the distance between the robot and the obstacle is monitored, and the counterweight block is adjusted to the front of the body before the robot climbs over the obstacle to move the center of gravity of the robot forward.

[0021] The above-mentioned tracked transport robot, wherein the center of gravity controller is based on the processing result of the visual SLAM algorithm. If it is determined that the obstacle ahead is a trench obstacle, it first determines whether the trench width exceeds the maximum trench crossing width under the robot's current load conditions. If it exceeds, the robot cannot pass, and the alarm prompts; if it can cross, based on the real-time position and posture estimation result of the visual SLAM, the distance between the robot and the front of the trench is monitored, and before the robot crosses the trench, the counterweight block is adjusted to the rear of the body to increase the suspended length of the front of the robot; the position and posture calculated by the binocular camera when the body exceeds the front of the trench is recorded, and the distance of the front of the robot exceeding the front of the trench is calculated. If the distance exceeds the trench width, the counterweight block is adjusted to the front of the body to increase the suspended length of the tail of the robot.

[0022] In order to better achieve the above-mentioned purpose, the present invention also provides a method for controlling the center of gravity of a crawler transport robot, which comprises the following steps:

[0023] S100, using a binocular camera to collect image data and depth data in front of the robot, and based on the visual SLAM algorithm, perform real-time estimation of the camera position and posture and three-dimensional mapping of the ground in front;

[0024] S200, judging whether there is an obstacle in front of the robot and the type of the obstacle based on the result of the three-dimensional mapping;

[0025] S300, if there is no obstacle, read the pressure data and angle data, calculate the center of gravity position of the whole machine under the current load, and calculate the robot's limit inclination angle under the current load condition. If the current inclination angle is close to the robot's limit inclination angle, the alarm will sound; otherwise, calculate the ideal center of gravity position when the traction force is maximum under the current posture of the robot, and adjust the counterweight block to make it reach the ideal center of gravity position;

[0026] S400, if the obstacle ahead is determined to be a vertical obstacle, the height of the vertical obstacle ahead is calculated, the pressure data and the angle data are read, the center of gravity position of the whole machine under the current load is calculated, and the maximum obstacle crossing height of the center of gravity position of the whole machine is calculated; it is determined whether the robot can climb over the height of the vertical obstacle under the current load condition, and if it cannot climb over, an alarm is sounded; if it can climb over, the counterweight is adjusted to the front of the robot body before the robot climbs over the obstacle;

[0027] S500, if the obstacle ahead is determined to be a trench obstacle, then the trench width is calculated, the pressure data and the angle data are read, the center of gravity position of the entire robot under the current load is calculated, and the maximum trench width at the current center of gravity position of the entire robot is calculated; it is determined whether the robot can cross the trench width under the current load, and if not, an alarm is sounded; if it can be crossed, the counterweight is adjusted to the rear of the robot body before the robot crosses the trench; and

[0028] S600, determining whether the distance that the robot exceeds the front edge of the trench is greater than the trench width, and if so, adjusting the counterweight to the front of the machine body; if not, adjusting the counterweight to the rear of the machine body.

[0029] The technical effects of the present invention are:

[0030] 1) The present invention can adjust the center of gravity position in real time according to the driving state of the robot in the hilly orchard and the load state of the loading platform, thereby improving the robot's driving stability and passability on slopes. When the robot performs transportation tasks, loading and unloading fruits will cause the weight of the loading platform to change, and the rolling of the fruit caused by the body tilting will also affect the real-time center of gravity position of the loading platform. The center of gravity controller in the center of gravity balancing device can calculate the weight of the loading platform and the center of gravity position in real time based on the data collected by the pressure sensor and the angle sensor. Since the size and weight of the robot body and the position and size of the counterweight block are known, the center of gravity position of the whole machine under the current counterweight block position can be calculated. The control conditions are that the combined force of the crawler supports on both sides is close to the same and the ground pressure ratio of the single-side crawler is close to the same, and the horizontal and vertical stepping motors are controlled to adjust the position of the counterweight block to increase the maximum traction of the crawler walking device, so as to improve the robot's driving stability and passability on slopes;

[0031] 2) The present invention can monitor and identify obstacles in front of the robot in real time based on the image information and depth information collected by the binocular camera in front of the robot body, and adjust the center of gravity position according to the type of obstacle, thereby improving the robot's ultimate obstacle crossing and ultimate trench crossing capabilities. When the robot performs a transportation task, if the binocular camera identifies that there is a vertical obstacle in front of the robot, the center of gravity controller will adjust the counterweight to the front of the body in advance before the robot climbs over the obstacle, thereby moving the robot's center of gravity forward, thereby increasing the robot's ultimate obstacle crossing height. If the binocular camera identifies that there is a trench in front of the robot, the center of gravity controller will adjust the counterweight to the rear of the body in advance before the robot crosses the trench, thereby moving the body's center of gravity backward and increasing the suspended length of the front of the robot. After the front of the robot crosses the trench, the center of gravity controller will adjust the counterweight to the front of the body, increasing the suspended length of the robot's tail, thereby increasing the robot's ultimate trench crossing width;

[0032] 3) The present invention can monitor the current driving state of the robot, the load state of the loading platform and the type of obstacles ahead in real time. If there is an imminent danger of tipping over or the obstacle ahead cannot be passed, the alarm will sound an alarm to remind the operator to operate with caution. When the robot performs a transportation task, the center of gravity controller can calculate the center of gravity position of the entire machine in real time based on the data collected by the pressure sensor and the angle sensor, and then deduce the limit safety angle of the robot's tipping over in the current state. If the current tilt angle of the robot is close to the calculated limit safety angle, the alarm will sound an alarm to remind the operator to operate with caution, thereby improving the driving operation safety of the crawler robot in hilly and mountainous orchards. The binocular camera at the front of the body can collect the image data and depth data of the robot in front in real time. The center of gravity controller estimates the real-time position and posture of the camera and builds a map of the road ahead based on the visual SLAM algorithm. If the robot cannot pass the obstacle ahead under the current load, the alarm will sound an alarm to remind the operator to operate with caution, thereby improving the obstacle crossing operation safety of the crawler robot in hilly and mountainous orchards.

[0033] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments, but is not intended to limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic structural diagram of a crawler transport robot according to an embodiment of the present invention;

[0035] Figure 2 This is a schematic diagram of the structure of a power device according to an embodiment of the present invention;

[0036] Figure 3 It is a schematic diagram of the structure of a transmission device according to an embodiment of the present invention;

[0037] Figure 4 This is a schematic diagram of the structure of a walking device according to an embodiment of the present invention;

[0038] Figure 5 It is a schematic structural diagram of a carrying device according to an embodiment of the present invention;

[0039] Figure 6 A schematic diagram of the installation position of a center of gravity balancing device according to an embodiment of the present invention;

[0040] Figure 7 This is a structural schematic diagram of a center of gravity balancing device according to an embodiment of the present invention;

[0041] Figure 8 A flow chart of a center of gravity control method according to an embodiment of the present invention;

[0042] Figures 9A-9H The figure is a schematic diagram of the center of gravity adjustment principle according to an embodiment of the present invention.

[0043] Among them, the reference numerals

[0044] 1 Body

[0045] 2 Carrying device

[0046] 21 Fruit Basket

[0047] 22 stage

[0048] 3 Walking device

[0049] 31 large tensioner

[0050] 32 small tensioner

[0051] 33 Loading wheel

[0052] 34 driving wheels

[0053] 35 support pulley

[0054] 36 spring suspension

[0055] 37 Tracks

[0056] 4 Power Plant

[0057] 41Battery

[0058] 42 Power Management Module

[0059] 43 Motor

[0060] 5 Transmission

[0061] 51 reducer

[0062] 52 bearing seat

[0063] 53 Power output shaft

[0064] 54 chain transmission mechanism

[0065] 6. Center of gravity balance device

[0066] 61 longitudinal slide rail

[0067] 62 first horizontal slide rail

[0068] 63 horizontal stepper motor

[0069] 64 Second horizontal slide rail

[0070] 65 counterweight

[0071] 66 longitudinal stepper motor

[0072] 67 Pressure Sensor DETAILED DESCRIPTION

[0073] The structural principle and working principle of the present invention are described in detail below in conjunction with the accompanying drawings:

[0074] See also Figure 1 , Figure 1 The schematic diagram of the structure of a crawler transport robot according to an embodiment of the present invention. The crawler transport robot of the present invention comprises a body 1 and a power device 4, a transmission device 5, a walking device 3, a carrying device 2 and a control device (not shown) installed on the body 1, wherein the transmission device 5 is connected to the power device 4 and the walking device 3 respectively, and the control device is connected to the power device 4; and further comprises a center of gravity balancing device 6, wherein the center of gravity balancing device 6 is located inside the body 1. The present invention realizes the walking action of the robot through the power device 4, the transmission device 5 and the walking device 3, realizes the fruit transportation through the carrying device 2, realizes the remote control walking of the robot through the control device, and adjusts the center of gravity in real time through the center of gravity balancing device 6 to improve the slope driving performance of the whole vehicle. The crawler transport robot can carry out fruit transportation operations in hilly and mountainous orchards, and has good driving performance on complex road conditions.

[0075] The control device of this embodiment includes a remote controller, a signal receiver and a walking controller. The control device is located inside the body 1. The signal receiver receives the remote controller signal in real time and inputs the received signal to the walking controller. The walking controller inputs the motor control signal to the driver according to the communication protocol, thereby controlling the start, stop and speed of the motor 43 to realize the walking control of the robot.

[0076] See also Figure 2 , Figure 2 This is a schematic diagram of the structure of the power device 4 of an embodiment of the present invention. The power device 4 of this embodiment includes a battery 41, a power management module 42, a driver and a motor 43. The battery 41 supplies power to the entire vehicle, the power management module 42 provides charging management and overvoltage, overcurrent, overtemperature and short circuit protection for the battery 41, the driver responds to external signals, controls the start, stop and speed of the motor 43, and provides overload, short circuit and undervoltage protection for the motor 43, and the motor 43 provides driving power for the whole vehicle to travel. The power device 4 is located inside the body 1, and the number of motors 43 is preferably two, which respectively provide driving power for the transmission device 5 and the travel device 3 on both sides of the body 1.

[0077] See also Figure 3 , Figure 3Schematic diagram of the transmission device 5 of an embodiment of the present invention. The transmission device 5 of this embodiment includes a reducer 51, a power output shaft 53 and a chain transmission mechanism 54. The reducer 51 is installed inside the machine body 1, the motor 43 is connected to the input end of the reducer 51, the power output shaft 53 is connected to the output end of the reducer 51, the power output shaft 53 is installed on the side wall of the machine body 1 through the bearing seat 52, the chain transmission mechanism 54 is located outside the machine body 1, the power output shaft 53 is connected to the chain transmission mechanism 54, the chain transmission mechanism 54 is connected to the driving wheel 34 of the walking mechanism, and the power output shaft 53 rotates to drive the corresponding walking mechanism to perform walking action.

[0078] See also Figure 4 , Figure 4 The schematic diagram of the structure of the walking device 3 of one embodiment of the present invention. The walking device 3 of this embodiment includes a driving wheel 34, a bearing wheel 33, a support wheel 35, a large tension wheel 31, a small tension wheel 32, a spring suspension 36 and a crawler 37. The spring suspension 36 is installed on both sides of the machine body 1 through a fixed shaft, and the driving wheel 34, the bearing wheel 33, the support wheel 35, the large tension wheel 31 and the small tension wheel 32 are installed on the spring suspension 36, wherein the driving wheel 34 is located near the tail of the machine body 1, connected to the power output shaft 53 through a chain transmission mechanism 54, and provides driving force for the movement of the walking device 3, the bearing wheel 33 is located near the bottom of the machine body 1, and bears most of the weight of the robot as a whole, the large tension wheel 31 and the small tension wheel 32 are located near the front of the machine body 1, and provide tension for the crawler 37, and the support wheel 35 is located near the top of the machine body 1, and supports the crawler 37.

[0079] See also Figure 5 , Figure 5 Schematic diagram of the structure of a load-bearing device 2 according to an embodiment of the present invention. The load-bearing device 2 according to this embodiment includes a loading platform 22 and a fruit basket 21. The loading platform 22 is located on the upper part of the machine body 1 and supports the fruit basket 21. The fruit basket 21 is placed inside the loading platform 22 and can be fixed to the loading platform 22 by ropes or the like. The size of the fruit basket 21 is determined according to the actual material transportation situation.

[0080] See also Figure 6 and Figure 7 , Figure 6 This is a schematic diagram of the installation position of the center of gravity balancing device 6 according to an embodiment of the present invention. Figure 7The center of gravity balancing device 6 of one embodiment of the present invention is a schematic diagram of the structure. The center of gravity balancing device 6 of this embodiment includes: a transverse slide rail, which is installed on the bracket inside the body 1, and a transverse stepper motor 63 is installed at one end of the transverse slide rail; a longitudinal slide rail 61, which is installed on the transverse slide rail and moves along the transverse slide rail, and a longitudinal stepper motor 66 is installed at one end of the longitudinal slide rail 61; a counterweight 65, which is installed on the longitudinal slide rail 61 and moves along the longitudinal slide rail 61; a pressure sensor 67, which is installed at the connection between the body 1 and the carrying device 2, and is used to monitor the pressure of the carrying device 2 on the body 1 in real time, and preferably four pressure sensors are installed at the connection between the upper part of the body 1 and the four corners of the bottom of the loading platform 22 of the carrying device 2, and monitor the pressure of the four corners of the bottom of the loading platform 22 on the body 1 in real time; an angle sensor (not shown in the figure), which is installed near the position inside the body 1 near the centroid, and is used to monitor the pitch, roll angle and other inclination changes of the body 1 in real time; a binocular camera (not shown in the figure), which is installed At the front of the body 1, it is used to monitor and identify obstacles in front of the robot in real time; and a center of gravity controller (not shown), which is installed in the body 1. The center of gravity controller includes an industrial computer and a stepper motor driver. The industrial computer is connected to the pressure sensor 67, the angle sensor and the binocular camera respectively, and receives the pressure data, angle data and image data collected by the pressure sensor 67, the angle sensor and the binocular camera in real time. The stepper motor driver is connected to the horizontal stepper motor 63 and the longitudinal stepper motor 66 respectively. The industrial computer inputs the control signal into the stepper motor driver according to the preset center of gravity control method, and the stepper motor driver drives the horizontal stepper motor 63 or the longitudinal stepper motor 66 to move accordingly. The counterweight block 65 moves in real time with the posture of the body 1 and the obstacles in front, so as to realize the real-time adjustment of the center of gravity of the robot and improve the driving passability and extreme obstacle crossing performance of the crawler transport robot in hilly and mountainous orchards.

[0081] In this embodiment, an alarm (not shown) is also included, which is connected to the industrial computer and can be located outside the body 1, and is used to alarm the robot tipping over during driving. When the robot's tilt angle approaches the limit safety angle under the current load or the robot cannot safely pass the obstacle ahead, the alarm will issue an alarm prompt. If the robot's tilt angle approaches the limit safety angle under the current load or the robot cannot safely pass the obstacle ahead during driving, the alarm will prompt the operator to operate with caution, thereby improving the operational safety of the crawler robot in hilly orchards.

[0082] In this embodiment, the counterweight 65, the longitudinal slide rail 61, and the transverse slide rail of the center of gravity balancing device 6 are all located inside the machine body 1. The material of the counterweight 65 is preferably a lead core with a stainless steel shell, and the weight of a single counterweight 65 is preferably about 20 kg. The number of counterweights 65 is determined according to the total weight of the whole machine. The shape of the counterweight 65 is preferably a "concave" shape, and it is fixed on the slide table of the longitudinal slide rail 61 by bolts and a pressure plate; the number of longitudinal slide rails 61 is preferably one, and a ball screw structure is adopted, and the ball screw can be driven by a longitudinal stepping motor 66 to realize the longitudinal sliding of the counterweight 65, and the longitudinal slide rail 61 is installed on the slide table of the transverse slide rail through a connecting plate. The longitudinal slide rail 61 includes a longitudinal slide rail, a longitudinal slide table and a ball screw. The ball screw and the longitudinal slide rail are respectively arranged parallel to the longitudinal slide table. The counterweight block 65 is installed on the longitudinal slide table. The longitudinal stepping motor 66 is connected to the ball screw and drives the ball screw to drive the counterweight block 65 to slide along the longitudinal slide rail. The transverse slide rail includes a first transverse slide rail 62 and a second transverse slide rail 64, both of which adopt a ball screw structure. The first transverse slide rail 62 includes a first transverse slide rail, a first transverse slide table and a screw. The screw can be driven by a transverse stepper motor 63 to realize the transverse sliding of the counterweight 65 and the longitudinal slide rail 61. The screw and the first transverse slide rail are respectively arranged parallel to the first transverse slide table. The transverse stepper motor 63 is connected to the screw and drives the screw to drive the longitudinal slide rail 61 and the counterweight 65 to slide along the first transverse slide rail; the second transverse slide rail 64 includes a second transverse slide rail and a second transverse slide table, which are used to support the longitudinal slide rail 61 and the counterweight 65 to prevent a single transverse slide rail from being unbalanced and affecting its service life. The first transverse slide rail 62 and the second transverse slide rail 64 are installed in parallel to the internal bracket of the body 1.

[0083] The center of gravity controller calculates the real-time center of gravity position of the robot according to the angle data and the pressure data, and takes the ground contact pressure of the crawlers 37 on both sides of the walking device 3 as the equal control condition, and drives the lateral stepper motor 63 and the longitudinal stepper motor 66 through the stepper motor driver to control the position of the counterweight block 65 to adjust the center of gravity of the whole machine. While calculating the real-time center of gravity position of the whole machine, the center of gravity controller calculates the robot's limit inclination angle under the current load condition. If the current inclination angle is close to the robot's limit inclination angle, the alarm will sound an alarm.

[0084] In this embodiment, the center of gravity controller performs real-time estimation of the camera position and posture and three-dimensional mapping of the front ground based on the visual SLAM algorithm according to the image data and depth data in front of the robot collected by the binocular camera, and judges whether there is an obstacle in front of the robot and the type of obstacle based on the result of the three-dimensional mapping. Wherein, the center of gravity controller is based on the processing result of the visual SLAM algorithm. If the obstacle in front is judged to be a vertical obstacle, it first judges whether the current height of the vertical obstacle exceeds the limit obstacle crossing height under the current load condition of the robot. If it exceeds, the robot cannot climb over it, and the alarm prompts; if it can climb over it, the distance between the robot and the obstacle is monitored based on the real-time position and posture estimation result of the visual SLAM, and the counterweight block 65 is adjusted to the front of the body 1 before the robot climbs over the obstacle to move the center of gravity of the robot forward. The center of gravity controller is based on the processing results of the visual SLAM algorithm. If it is determined that the obstacle ahead is a trench obstacle, it first determines whether the trench width exceeds the maximum trench crossing width under the robot's current load conditions. If it exceeds, the robot cannot pass, and the alarm prompts; if it can cross, based on the real-time position and posture estimation results of the visual SLAM, the distance between the robot and the front of the trench is monitored, and before the robot crosses the trench, the counterweight block 65 is adjusted to the rear of the body 1 to increase the suspended length of the front of the robot; the position and posture calculated by the binocular camera when the body 1 exceeds the front of the trench is recorded, and the distance of the front of the robot exceeding the front of the trench is calculated. If the distance exceeds the trench width, the counterweight block 65 is adjusted to the front of the body 1 to increase the suspended length of the tail of the robot.

[0085] See also Figure 8 , Figure 8 The center of gravity control method of an embodiment of the present invention is a flow chart. The center of gravity control method of the crawler transport robot of the present invention comprises the following steps:

[0086] Step S100: using a binocular camera to collect image data and depth data in front of the robot, and based on a visual SLAM algorithm, performing real-time estimation of the camera position and posture and three-dimensional mapping of the front ground;

[0087] Step S200: judging whether there is an obstacle in front of the robot and the type of the obstacle based on the result of the three-dimensional mapping;

[0088] Step S300: If there is no obstacle, the pressure data and angle data are read, and the center of gravity position of the whole machine under the current load is calculated, and the robot's limit inclination angle under the current load condition is calculated. If the current inclination angle is close to the robot's limit inclination angle, the alarm is sounded; otherwise, the ideal center of gravity position when the traction force is maximum under the current posture of the robot is calculated, and the counterweight block 65 is adjusted to make it reach the ideal center of gravity position;

[0089] Step S400: If the obstacle ahead is determined to be a vertical obstacle, the height of the vertical obstacle ahead is calculated, the pressure data and the angle data are read, the center of gravity position of the whole machine under the current load is calculated, and the maximum obstacle crossing height of the center of gravity position of the whole machine is calculated; it is determined whether the robot can climb over the height of the vertical obstacle under the current load condition, and if it cannot climb over, the alarm is sounded; if it can climb over, the counterweight block 65 is adjusted to the front of the body 1 before the robot climbs over the obstacle;

[0090] Step S500: if the obstacle ahead is determined to be a trench obstacle, the trench width is calculated, the pressure data and the angle data are read, the center of gravity position of the robot under the current load is calculated, and the maximum trench width at the current center of gravity position of the robot is calculated; it is determined whether the robot can cross the trench width under the current load, and if not, an alarm is sounded; if it can be crossed, the counterweight block 65 is adjusted to the rear of the body 1 before the robot crosses the trench; and

[0091] Step S600, determine whether the distance that the robot exceeds the front edge of the trench is greater than the trench width. If so, adjust the counterweight block 65 to the front of the body 1; if not, adjust the counterweight block 65 to the rear of the body 1.

[0092] When the robot performs a walking task, the remote controller transmits a robot walking control signal, and the walking controller sends a motor control signal to the driver through the communication protocol according to the robot walking control signal received by the signal receiver, so as to realize the start, stop, and rotation control of the motors 43 on the left and right sides of the robot. The motors 43 on the left and right sides provide rotational driving force for the driving wheels 34 of the walking devices 3 on the left and right sides through the reducer 51, the power output shaft 53, and the chain transmission mechanism 54, and the walking device 3 performs the robot walking task, thereby realizing the walking action control of the robot.

[0093] Before the robot performs the transportation task, the fruit basket 21 filled with fruits is placed in the loading platform 22 and fixed by ropes. When the robot performs the transportation task, the angle sensor of the center of gravity balancing device 6 detects the pitch and roll status of the robot in real time, and transmits the angle signal to the center of gravity controller. The four pressure sensors 67 of the center of gravity balancing device 6 detect the pressure of the loading platform 22 on the body 1 in real time, and transmit the pressure signal to the center of gravity controller. Based on the force balance and torque balance principles in theoretical mechanics, the center of gravity controller can calculate the real-time center of gravity position of the loading platform 22 according to the angle signal and the pressure signal. Since the weight and size of the robot body are known, the weight of the transverse slide rail, the longitudinal slide rail 61, and the counterweight block 65 in the center of gravity self-balancing device are known, and the position of the counterweight block 65 is known, the real-time center of gravity position of the robot (including the load of the loading platform 22) can be calculated based on the above data. Since the current posture of the body 1 can be obtained in real time through the angle sensor, according to the force balance and torque balance principles in theoretical mechanics, the robot's extreme pitch and roll angles under the current load conditions are deduced, and the control strategy is to make the ground pressure ratio of the tracks 37 on both sides close to the same. The center of gravity controller drives the position of the counterweight block 65 through the horizontal and vertical stepper motors 63 and 66 to adjust the center of gravity of the whole machine. After the center of gravity of the whole machine is adjusted by the center of gravity balance device 6, the ground pressure ratio of the tracks 37 on both sides is close to the same, which can effectively avoid the overall slippage of the single-side track 37 or the slippage of the local track 37, improve the maximum traction of the track 37, and thus improve the passing performance of the crawler transport robot in complex terrain. Once the current tilt angle of the robot is close to the robot's extreme pitch and roll angles, the alarm will alarm to remind the operator to operate cautiously to avoid the occurrence of rollover, thereby improving the driving safety of the crawler transport robot in complex terrain.

[0094] See also Figures 9A-9H , Figures 9A-9H Schematic diagram of the center of gravity adjustment principle of an embodiment of the present invention, that is, the center of gravity position of the robot in different driving states, wherein: Fig.9A To go up the stairs, Fig. 9B To go down the stairs, Fig. 9C For uphill, Fig.9D For downhill, Fig.9E is a left slope, Fig.9F is the right slope, Figure 9G , 9HThe figure is a schematic diagram of the center of gravity position when crossing an obstacle and a trench. When the robot performs a transport task, the binocular camera of the center of gravity self-balancing device collects image data and depth data in front of the robot in real time, and transmits the data to the center of gravity controller. The center of gravity controller estimates the camera position and posture in real time and builds a three-dimensional map of the ground in front based on the visual SLAM algorithm, and determines whether there is an obstacle in front of the robot and the type of obstacle based on the mapping result. If the mapping result based on the visual SLAM algorithm is a smooth ground, that is, there is no obstacle, the center of gravity controller uses the ground pressure ratio of the tracks 37 on both sides as the control strategy to adjust the center of gravity position of the whole machine; if the mapping result based on the visual SLAM algorithm is a vertical obstacle such as a step, first determine whether the current height of the vertical obstacle exceeds the limit obstacle crossing height under the current load condition of the robot. If it exceeds, the robot cannot climb over, and the alarm prompts the driver to operate with caution. If it can climb over, the distance between the robot and the obstacle is monitored based on the real-time position and posture estimation result of the visual SLAM. The center of gravity controller will adjust the counterweight block 65 to the front of the body 1 in advance before the robot climbs over the obstacle. , and then the robot's center of gravity moves forward, thereby increasing the robot's maximum obstacle crossing height; if the mapping result based on the visual SLAM algorithm is an obstacle such as a trench, first determine whether the trench width exceeds the robot's maximum trench crossing width under the current load condition. If it exceeds, the robot cannot pass, and the alarm prompts the driver to operate with caution. If it can cross, then based on the real-time position and posture estimation result of the visual SLAM, monitor the distance between the robot and the front edge of the trench. The center of gravity controller will adjust the counterweight block 65 to the rear of the body 1 in advance before the robot crosses the trench, so that the center of gravity of the body 1 moves backward, increases the suspended length of the front of the robot, and prevents the robot's front from falling into the trench. Record the position and posture calculated by the binocular camera when the body 1 exceeds the front edge of the trench, and calculate the distance that the front of the robot exceeds the front edge of the trench. If the distance exceeds the trench width, it proves that the front walking device 3 of the machine has contacted the rear edge of the trench, then the center of gravity controller will adjust the counterweight block 65 to the front of the body 1, increase the suspended length of the robot's tail, and prevent the robot's tail from falling into the trench, thereby increasing the robot's maximum trench crossing width.

[0095] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A crawler transport robot, comprising a body and a power device, a transmission device, a walking device, a carrying device and a control device installed on the body, wherein the transmission device is connected to the power device and the walking device respectively, and the control device is connected to the power device, characterized in that: It also includes a center of gravity balancing device, which is located in the machine body and includes: A transverse slide rail is installed on a bracket in the body, and a transverse stepping motor is installed at one end of the transverse slide rail; A longitudinal slide rail is installed on the transverse slide rail and moves along the transverse slide rail, and a longitudinal stepping motor is installed at one end of the longitudinal slide rail; A counterweight block is mounted on the longitudinal slide rail and moves along the longitudinal slide rail; A pressure sensor, installed at the connection between the body and the carrying device, for real-time monitoring of the pressure of the carrying device on the body; An angle sensor, installed near the centroid of the machine body, for real-time monitoring of the inclination angle change of the machine body; A binocular camera is installed at the front of the robot body and is used for real-time monitoring and identifying obstacles in front of the robot; A center of gravity controller is installed in the body, and the center of gravity controller includes an industrial computer and a stepper motor driver. The industrial computer is connected to the pressure sensor, the angle sensor and the binocular camera respectively, and receives the pressure data, angle data and image data collected by the pressure sensor, the angle sensor and the binocular camera in real time. The stepper motor driver is connected to the horizontal stepper motor and the vertical stepper motor respectively. The industrial computer inputs the control signal into the stepper motor driver according to the preset center of gravity control method, and the stepper motor driver drives the horizontal stepper motor or the vertical stepper motor to move accordingly. The counterweight block moves with the machine. The robot's body posture and the obstacle in front move in real time to achieve real-time adjustment of the robot's center of gravity; and an alarm, connected to the industrial computer, for the robot to tip over during driving. When the robot's tilt angle approaches the limit safety angle under the current load or the robot cannot safely pass the obstacle in front, the alarm will issue an alarm prompt; wherein, the center of gravity controller calculates the real-time center of gravity position of the robot according to the angle data and pressure data, and takes the ground contact pressure of the tracks on both sides of the walking device to be equal as the control condition, and drives the lateral stepper motor and the longitudinal stepper motor through the stepper motor driver to control the position of the counterweight to adjust the center of gravity of the whole machine; The center of gravity controller performs real-time estimation of the camera position and posture and three-dimensional mapping of the front ground based on the visual SLAM algorithm according to the image data and depth data in front of the robot collected by the binocular camera, and determines whether there is an obstacle in front of the robot and the type of obstacle based on the result of the three-dimensional mapping; The center of gravity controller is based on the processing results of the visual SLAM algorithm. If it is determined that the obstacle ahead is a vertical obstacle, it first determines whether the current height of the vertical obstacle exceeds the maximum obstacle crossing height under the robot's current load conditions. If it exceeds, the robot cannot climb over it, and the alarm device gives an alarm prompt; if it can climb over it, based on the real-time position and posture estimation results of the visual SLAM, the distance between the robot and the obstacle is monitored, and the counterweight block is adjusted to the front of the robot body before the robot climbs over the obstacle to move the center of gravity of the robot forward.

2. The crawler transport robot according to claim 1, characterized in that: The longitudinal slide rail includes a longitudinal slide rail, a longitudinal slide table and a ball screw. The ball screw and the longitudinal slide rail are respectively arranged parallel to the longitudinal slide table. The counterweight block is installed on the longitudinal slide table. The longitudinal stepping motor is connected to the ball screw and drives the ball screw to drive the counterweight block to slide along the longitudinal slide rail.

3. The crawler transport robot according to claim 2, characterized in that: The transverse slide rail includes a first transverse slide rail and a second transverse slide rail, the first transverse slide rail includes a first transverse slide rail, a first transverse slide table and a lead screw, the lead screw and the first transverse slide rail are respectively arranged parallel to the first transverse slide table, the transverse stepping motor is connected to the lead screw, and drives the lead screw to drive the longitudinal slide rail and the counterweight block to slide along the first transverse slide rail; the second transverse slide rail includes a second transverse slide rail and a second transverse slide table, which are used to support the longitudinal slide rail and the counterweight block.

4. The crawler transport robot according to claim 1, characterized in that: The center of gravity controller calculates the robot's limit inclination angle under the current load condition while calculating the real-time center of gravity position of the whole machine. If the current inclination angle is close to the robot's limit inclination angle, the alarm will sound an alarm.

5. The crawler transport robot according to claim 1, characterized in that: The center of gravity controller processes the result based on the visual SLAM algorithm. If it is determined that the obstacle ahead is a trench obstacle, it first determines whether the trench width exceeds the maximum trench width under the current load condition of the robot. If it exceeds, the robot cannot pass through, and the alarm will sound an alarm. If it can be crossed, the distance between the robot and the front of the trench is monitored based on the real-time position and posture estimation results of visual SLAM, and the counterweight block is adjusted to the rear of the body before the robot crosses the trench to increase the hanging length of the front of the robot; the position and posture calculated by the binocular camera when the body exceeds the front of the trench is recorded, and the distance that the front of the robot exceeds the front of the trench is calculated. If the distance exceeds the width of the trench, the counterweight block is adjusted to the front of the body to increase the hanging length of the tail of the robot.

6. A method for controlling the center of gravity of a crawler transport robot, characterized in that: The method for controlling the center of gravity of the crawler transport robot according to any one of claims 1 to 5 comprises the following steps: S100, using a binocular camera to collect image data and depth data in front of the robot, and based on the visual SLAM algorithm, perform real-time estimation of the camera position and posture and three-dimensional mapping of the ground in front; S200, judging whether there is an obstacle in front of the robot and the type of the obstacle based on the result of the three-dimensional mapping; S300, if there is no obstacle, read the pressure data and angle data, calculate the center of gravity position of the whole machine under the current load, and calculate the robot's limit inclination angle under the current load condition. If the current inclination angle is close to the robot's limit inclination angle, the alarm will sound; otherwise, calculate the ideal center of gravity position when the traction force is maximum under the current posture of the robot, and adjust the counterweight block to make it reach the ideal center of gravity position; S400, if the obstacle ahead is determined to be a vertical obstacle, the height of the vertical obstacle ahead is calculated, the pressure data and the angle data are read, the center of gravity position of the whole machine under the current load is calculated, and the maximum obstacle crossing height of the center of gravity position of the whole machine is calculated; it is determined whether the robot can climb over the height of the vertical obstacle under the current load condition, and if it cannot climb over, an alarm is sounded; if it can climb over, the counterweight is adjusted to the front of the robot body before the robot climbs over the obstacle; S500, if the obstacle ahead is determined to be a trench obstacle, then the trench width is calculated, the pressure data and the angle data are read, the center of gravity position of the entire robot under the current load is calculated, and the maximum trench width at the current center of gravity position of the entire robot is calculated; it is determined whether the robot can cross the trench width under the current load, and if not, an alarm is sounded; if it can be crossed, the counterweight is adjusted to the rear of the robot body before the robot crosses the trench; and S600, determining whether the distance that the robot exceeds the front edge of the trench is greater than the trench width, and if so, adjusting the counterweight to the front of the machine body; if not, adjusting the counterweight to the rear of the machine body.

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